Atmosphere-ocean coupling controlling Early Pleistocene changes in the deep carbon storage of the Eastern Equatorial Pacific (EEP)

• Main Authors: Povea, Patricia, Cacho, Isabel, Moreno Caballud, Ana, Pena, Leopoldo, Menéndez, Melisa, Calvo, Eva María, Canals, Miquel, Robinson, Rebecca S., Flores, José Abel, Méndez, Fernando J.
• Format: Conference Object
• Language: unknown
• Published: Association for the Sciences of Limnology and Oceanography 2015
• Subjects: Southern Ocean
• Online Access: http://hdl.handle.net/10261/135803

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, Spain EEP (ODP 1240) provides a unique opportunity to reconstruct coupled changes in the atmosphere-ocean systems through the analysis of lithic and biogenic components, from 1.6 to 2.2 Ma. The methodology combines δ18O in benthic foraminifera, Uvigerina spp. abundance, Sibio, TOC, lithic fraction and Fe-XRF composition. Throughout the studied period, can be clearly distinguished the glacial periods prior to 1.85 Ma, dominated by low Fe and sparse lithogenic grains, poorly sorted and coarser, which could reflect the dominance of stronger local trade winds with a northward ITCZ position. Surprisingly, high TOC and Si values also occurred during these low-Fe periods, albeit Uvigerina spp. did not benefit from them, indicating that this diatom productivity was not dust stimulated. These intervals correspond to Laminated Diatom Oozes (LDO), suggesting an enhanced upwelling system of rich-silica waters probably from the Southern Ocean and would have promoted a very efficient OM transport towards the deep sea, changing drastically the ecosystem. Moreover, glacial periods after 1.85 Ma show a Fe-dust stimulated productivity with a reduced C flux towards the deep ocean that stimulated the Uvigerina spp. development Peer Reviewed